The prior art fire fighting trainer is described in U.S. Pat. Nos. 5,055,050, issued Oct. 8, 1991, and 4,861,270, issued Aug. 29, 1989, assigned to the same assignee as this application.
The prior art fire fighting trainer has a burner system and a support for the burner system, the burner system includes a delivery pipe having holes for ejecting propane to form a flame, a control connected to the delivery pipe, a pilot unit for lighting the ejected propane to form a flame, a control connected to the delivery pipe, and a pilot unit for lighting the ejected propane. The prior art system uses pressurized propane liquid which passes as vapor bubbles through a layer of gravel or water and then collects as propane vapor on the surface where it can be ignited to simulate an aircraft crash liquid fuel flames.
Such trainers are utilized outside exposed to normal climate conditions. When water is utilized in such a system it has certain disadvantages. One disadvantage is that there is excessive bubbling on the surface and applying sensors to determine the extinguishing of the flame is more difficult caused by the agitated water. It also has a relatively high noise level. Water also requires the use of expensive grating over the water to allowing the fire fighting trainers to walk over the surface. Aggregates such as gravel have the advantage of good vapor dispersion while also providing a firm surface on which the fire fighter trainess can walk. One disadvantage of the aggregate is that it does not protect the underlying surfaces or equipment from radiant heat as well as water.